<?php

/**********************************************************************
*  Author: Justin Vincent (jv@vip.ie)
*  Web...: http://justinvincent.com
*  Name..: ezSQL
*  Desc..: ezSQL Core module - database abstraction library to make
*          it very easy to deal with databases. ezSQLcore can not be used by 
*          itself (it is designed for use by database specific modules).
*
*/

/**********************************************************************
*  ezSQL Constants
*/

define('EZSQL_VERSION','2.17');
define('OBJECT','OBJECT',true);
define('ARRAY_A','ARRAY_A',true);
define('ARRAY_N','ARRAY_N',true);

/**********************************************************************
*  Core class containg common functions to manipulate query result
*  sets once returned
*/

class ezSQLcore
{

        var $trace            = false;  // same as $debug_all
        var $debug_all        = false;  // same as $trace
        var $debug_called     = false;
        var $vardump_called   = false;
        var $show_errors      = true;
        var $num_queries      = 0;
        var $last_query       = null;
        var $last_error       = null;
        var $col_info         = null;
        var $captured_errors  = array();
        var $cache_dir        = false;
        var $cache_queries    = false;
        var $cache_inserts    = false;
        var $use_disk_cache   = false;
        var $cache_timeout    = 24; // hours
        var $timers           = array();
        var $total_query_time = 0;
        var $db_connect_time  = 0;
        var $trace_log        = array();
        var $use_trace_log    = false;
        var $sql_log_file     = false;
        var $do_profile       = false;
        var $profile_times    = array();

        // == TJH == default now needed for echo of debug function
        var $debug_echo_is_on = true;

        /**********************************************************************
        *  Constructor
        */

        function ezSQLcore()
        {
        }

        /**********************************************************************
        *  Print SQL/DB error - over-ridden by specific DB class
        */

        function register_error($err_str)
        {
                // Keep track of last error
                $this->last_error = $err_str;

                // Capture all errors to an error array no matter what happens
                $this->captured_errors[] = array
                (
                        'error_str' => $err_str,
                        'query'     => $this->last_query
                );
        }

        /**********************************************************************
        *  Turn error handling on or off..
        */

        function show_errors()
        {
                $this->show_errors = true;
        }

        function hide_errors()
        {
                $this->show_errors = false;
        }

        /**********************************************************************
        *  Kill cached query results
        */

        function flush()
        {
                // Get rid of these
                $this->last_result = null;
                $this->col_info = null;
                $this->last_query = null;
                $this->from_disk_cache = false;
        }

        /**********************************************************************
        *  Get one variable from the DB - see docs for more detail
        */

        function get_var($query=null,$x=0,$y=0)
        {

                // Log how the function was called
                $this->func_call = "\$db->get_var(\"$query\",$x,$y)";

                // If there is a query then perform it if not then use cached results..
                if ( $query )
                {
                        $this->query($query);
                }

                // Extract var out of cached results based x,y vals
                if ( $this->last_result[$y] )
                {
                        $values = array_values(get_object_vars($this->last_result[$y]));
                }

                // If there is a value return it else return null
                return (isset($values[$x]) && $values[$x]!=='')?$values[$x]:null;
        }

        /**********************************************************************
        *  Get one row from the DB - see docs for more detail
        */

        function get_row($query=null,$output=OBJECT,$y=0)
        {

                // Log how the function was called
                $this->func_call = "\$db->get_row(\"$query\",$output,$y)";

                // If there is a query then perform it if not then use cached results..
                if ( $query )
                {
                        $this->query($query);
                }

                // If the output is an object then return object using the row offset..
                if ( $output == OBJECT )
                {
                        return $this->last_result[$y]?$this->last_result[$y]:null;
                }
                // If the output is an associative array then return row as such..
                elseif ( $output == ARRAY_A )
                {
                        return $this->last_result[$y]?get_object_vars($this->last_result[$y]):null;
                }
                // If the output is an numerical array then return row as such..
                elseif ( $output == ARRAY_N )
                {
                        return $this->last_result[$y]?array_values(get_object_vars($this->last_result[$y])):null;
                }
                // If invalid output type was specified..
                else
                {
                        $this->print_error(" \$db->get_row(string query, output type, int offset) -- Output type must be one of: OBJECT, ARRAY_A, ARRAY_N");
                }

        }

        /**********************************************************************
        *  Function to get 1 column from the cached result set based in X index
        *  see docs for usage and info
        */

        function get_col($query=null,$x=0)
        {

                $new_array = array();

                // If there is a query then perform it if not then use cached results..
                if ( $query )
                {
                        $this->query($query);
                }

                // Extract the column values
                for ( $i=0; $i < count($this->last_result); $i++ )
                {
                        $new_array[$i] = $this->get_var(null,$x,$i);
                }

                return $new_array;
        }


        /**********************************************************************
        *  Return the the query as a result set - see docs for more details
        */

        function get_results($query=null, $output = OBJECT)
        {

                // Log how the function was called
                $this->func_call = "\$db->get_results(\"$query\", $output)";

                // If there is a query then perform it if not then use cached results..
                if ( $query )
                {
                        $this->query($query);
                }

                // Send back array of objects. Each row is an object
                if ( $output == OBJECT )
                {
                        return $this->last_result;
                }
                elseif ( $output == ARRAY_A || $output == ARRAY_N )
                {
                        if ( $this->last_result )
                        {
                                $i=0;
                                foreach( $this->last_result as $row )
                                {

                                        $new_array[$i] = get_object_vars($row);

                                        if ( $output == ARRAY_N )
                                        {
                                                $new_array[$i] = array_values($new_array[$i]);
                                        }

                                        $i++;
                                }

                                return $new_array;
                        }
                        else
                        {
                                return null;
                        }
                }
        }


        /**********************************************************************
        *  Function to get column meta data info pertaining to the last query
        * see docs for more info and usage
        */

        function get_col_info($info_type="name",$col_offset=-1)
        {

                if ( $this->col_info )
                {
                        if ( $col_offset == -1 )
                        {
                                $i=0;
                                foreach($this->col_info as $col )
                                {
                                        $new_array[$i] = $col->{$info_type};
                                        $i++;
                                }
                                return $new_array;
                        }
                        else
                        {
                                return $this->col_info[$col_offset]->{$info_type};
                        }

                }

        }

        /**********************************************************************
        *  store_cache
        */

        function store_cache($query,$is_insert)
        {

                // The would be cache file for this query
                $cache_file = $this->cache_dir.'/'.md5($query);

                // disk caching of queries
                if ( $this->use_disk_cache && ( $this->cache_queries && ! $is_insert ) || ( $this->cache_inserts && $is_insert ))
                {
                        if ( ! is_dir($this->cache_dir) )
                        {
                                $this->register_error("Could not open cache dir: $this->cache_dir");
                                $this->show_errors ? trigger_error("Could not open cache dir: $this->cache_dir",E_USER_WARNING) : null;
                        }
                        else
                        {
                                // Cache all result values
                                $result_cache = array
                                (
                                        'col_info' => $this->col_info,
                                        'last_result' => $this->last_result,
                                        'num_rows' => $this->num_rows,
                                        'return_value' => $this->num_rows,
                                );
                                error_log ( serialize($result_cache), 3, $cache_file);
                        }
                }

        }

        /**********************************************************************
        *  get_cache
        */

        function get_cache($query)
        {

                // The would be cache file for this query
                $cache_file = $this->cache_dir.'/'.md5($query);

                // Try to get previously cached version
                if ( $this->use_disk_cache && file_exists($cache_file) )
                {
                        // Only use this cache file if less than 'cache_timeout' (hours)
                        if ( (time() - filemtime($cache_file)) > ($this->cache_timeout*3600) )
                        {
                                unlink($cache_file);
                        }
                        else
                        {
                                $result_cache = unserialize(file_get_contents($cache_file));

                                $this->col_info = $result_cache['col_info'];
                                $this->last_result = $result_cache['last_result'];
                                $this->num_rows = $result_cache['num_rows'];

                                $this->from_disk_cache = true;

                                // If debug ALL queries
                                $this->trace || $this->debug_all ? $this->debug() : null ;

                                return $result_cache['return_value'];
                        }
                }

        }

        /**********************************************************************
        *  Dumps the contents of any input variable to screen in a nicely
        *  formatted and easy to understand way - any type: Object, Var or Array
        */

        function vardump($mixed='')
        {

                // Start outup buffering
                ob_start();

                echo "<p><table><tr><td bgcolor=ffffff><blockquote><font color=000090>";
                echo "<pre><font face=arial>";

                if ( ! $this->vardump_called )
                {
                        echo "<font color=800080><b>ezSQL</b> (v".EZSQL_VERSION.") <b>Variable Dump..</b></font>\n\n";
                }

                $var_type = gettype ($mixed);
                print_r(($mixed?$mixed:"<font color=red>No Value / False</font>"));
                echo "\n\n<b>Type:</b> " . ucfirst($var_type) . "\n";
                echo "<b>Last Query</b> [$this->num_queries]<b>:</b> ".($this->last_query?$this->last_query:"NULL")."\n";
                echo "<b>Last Function Call:</b> " . ($this->func_call?$this->func_call:"None")."\n";
                echo "<b>Last Rows Returned:</b> ".count($this->last_result)."\n";
                echo "</font></pre></font></blockquote></td></tr></table>".$this->donation();
                echo "\n<hr size=1 noshade color=dddddd>";

                // Stop output buffering and capture debug HTML
                $html = ob_get_contents();
                ob_end_clean();

                // Only echo output if it is turned on
                if ( $this->debug_echo_is_on )
                {
                        echo $html;
                }

                $this->vardump_called = true;

                return $html;

        }

        /**********************************************************************
        *  Alias for the above function
        */

        function dumpvar($mixed)
        {
                $this->vardump($mixed);
        }

        /**********************************************************************
        *  Displays the last query string that was sent to the database & a
        * table listing results (if there were any).
        * (abstracted into a seperate file to save server overhead).
        */

        function debug($print_to_screen=true)
        {

                // Start outup buffering
                ob_start();

                echo "<blockquote>";

                // Only show ezSQL credits once..
                if ( ! $this->debug_called )
                {
                        echo "<font color=800080 face=arial size=2><b>ezSQL</b> (v".EZSQL_VERSION.") <b>Debug..</b></font><p>\n";
                }

                if ( $this->last_error )
                {
                        echo "<font face=arial size=2 color=000099><b>Last Error --</b> [<font color=000000><b>$this->last_error</b></font>]<p>";
                }

                if ( $this->from_disk_cache )
                {
                        echo "<font face=arial size=2 color=000099><b>Results retrieved from disk cache</b></font><p>";
                }

                echo "<font face=arial size=2 color=000099><b>Query</b> [$this->num_queries] <b>--</b> ";
                echo "[<font color=000000><b>$this->last_query</b></font>]</font><p>";

                        echo "<font face=arial size=2 color=000099><b>Query Result..</b></font>";
                        echo "<blockquote>";

                if ( $this->col_info )
                {

                        // =====================================================
                        // Results top rows

                        echo "<table cellpadding=5 cellspacing=1 bgcolor=555555>";
                        echo "<tr bgcolor=eeeeee><td nowrap valign=bottom><font color=555599 face=arial size=2><b>(row)</b></font></td>";


                        for ( $i=0; $i < count($this->col_info); $i++ )
                        {
                                echo "<td nowrap align=left valign=top><font size=1 color=555599 face=arial>{$this->col_info[$i]->type} {$this->col_info[$i]->max_length}</font><br><span style='font-family: arial; font-size: 10pt; font-weight: bold;'>{$this->col_info[$i]->name}</span></td>";
                        }

                        echo "</tr>";

                        // ======================================================
                        // print main results

                if ( $this->last_result )
                {

                        $i=0;
                        foreach ( $this->get_results(null,ARRAY_N) as $one_row )
                        {
                                $i++;
                                echo "<tr bgcolor=ffffff><td bgcolor=eeeeee nowrap align=middle><font size=2 color=555599 face=arial>$i</font></td>";

                                foreach ( $one_row as $item )
                                {
                                        echo "<td nowrap><font face=arial size=2>$item</font></td>";
                                }

                                echo "</tr>";
                        }

                } // if last result
                else
                {
                        echo "<tr bgcolor=ffffff><td colspan=".(count($this->col_info)+1)."><font face=arial size=2>No Results</font></td></tr>";
                }

                echo "</table>";

                } // if col_info
                else
                {
                        echo "<font face=arial size=2>No Results</font>";
                }

                echo "</blockquote></blockquote>".$this->donation()."<hr noshade color=dddddd size=1>";

                // Stop output buffering and capture debug HTML
                $html = ob_get_contents();
                ob_end_clean();

                // Only echo output if it is turned on
                if ( $this->debug_echo_is_on && $print_to_screen)
                {
                        echo $html;
                }

                $this->debug_called = true;

                return $html;

        }

        /**********************************************************************
        *  Naughty little function to ask for some remuniration!
        */

        function donation()
        {
                return "<font size=1 face=arial color=000000>If ezSQL has helped <a href=\"https://www.paypal.com/xclick/business=justin%40justinvincent.com&item_name=ezSQL&no_note=1&tax=0\" style=\"color: 0000CC;\">make a donation!?</a> &nbsp;&nbsp;<!--[ go on! you know you want to! ]--></font>";
        }

        /**********************************************************************
        *  Timer related functions
        */

        function timer_get_cur()
        {
                list($usec, $sec) = explode(" ",microtime());
                return ((float)$usec + (float)$sec);
        }

        function timer_start($timer_name)
        {
                $this->timers[$timer_name] = $this->timer_get_cur();
        }

        function timer_elapsed($timer_name)
        {
                return round($this->timer_get_cur() - $this->timers[$timer_name],2);
        }

        function timer_update_global($timer_name)
        {
                if ( $this->do_profile )
                {
                        $this->profile_times[] = array
                        (
                                'query' => $this->last_query,
                                'time' => $this->timer_elapsed($timer_name)
                        );
                }

                $this->total_query_time += $this->timer_elapsed($timer_name);
        }

        /**********************************************************************
        * Creates a SET nvp sql string from an associative array (and escapes all values)
        *
        *  Usage:
        *
        *     $db_data = array('login'=>'jv','email'=>'jv@vip.ie', 'user_id' => 1, 'created' => 'NOW()');
        *
        *     $db->query("INSERT INTO users SET ".$db->get_set($db_data));
        *
        *     ...OR...
        *
        *     $db->query("UPDATE users SET ".$db->get_set($db_data)." WHERE user_id = 1");
        *
        * Output:
        *
        *     login = 'jv', email = 'jv@vip.ie', user_id = 1, created = NOW()
        */

        function get_set($parms)
        {		
                $sql = '';
                foreach ( $parms as $field => $val )
                {
                        if ( $val === 'true' ) $val = 1;
                        if ( $val === 'false' ) $val = 0;

                        if ( $val == 'NOW()' )
                        {
                                $sql .= "$field = ".$this->escape($val).", ";
                        }
                        else
                        {
                                $sql .= "$field = '".$this->escape($val)."', ";
                        }
                }

                return substr($sql,0,-2);
        }

}
